John Wesley on Genesis 16:8

And he said, Hagar, Sarai's maid - As a check to her pride. Though she was Abram's wife, yet he calls her Sarai's maid to humble her. As a rebuke to her flight. Sarai's maid ought to be in Sarai's tent, and not wandering in the wilderness. Whence comest thou - Consider that thou art running away both from the duty thou wast bound to, and the privileges thou wast blest with, in Abram's tent. And Whither wilt thou go? - Thou art running thyself into sin in Egypt; if she return to that people, she will return to their gods. And she said, I flee from the face of my mistress - She acknowledges her fault in fleeing from her mistress; and yet, excuses it, that it was from the face, or displeasure, of her mistress.